From 045d9ec2d2b7ead102ce3023122e62e89101afe6 Mon Sep 17 00:00:00 2001
From: tobtoht <thotbot@protonmail.com>
Date: Wed, 27 Jan 2021 00:55:27 +0100
Subject: [PATCH] Multi destination transactions

---
 src/appcontext.cpp            |  37 +++++++--
 src/appcontext.h              |   9 +-
 src/dialog/txconfadvdialog.ui |   8 +-
 src/dialog/txconfdialog.cpp   |   3 +-
 src/dialog/txconfdialog.h     |   3 +-
 src/libwalletqt/Wallet.cpp    |  44 +++++++++-
 src/libwalletqt/Wallet.h      |  11 ++-
 src/main.cpp                  |   1 +
 src/mainwindow.cpp            |  24 +++++-
 src/mainwindow.h              |   3 +-
 src/mainwindow.ui             |   8 +-
 src/sendwidget.cpp            |  62 ++++++++++++--
 src/sendwidget.h              |   4 +-
 src/sendwidget.ui             |  13 +--
 src/utils/xmrtoorder.cpp      |   4 +-
 src/utils/xmrtoorder.h        |   2 +-
 src/widgets/PayToEdit.cpp     | 150 ++++++++++++++++++++++++++++++++++
 src/widgets/PayToEdit.h       |  70 ++++++++++++++++
 18 files changed, 411 insertions(+), 45 deletions(-)
 create mode 100644 src/widgets/PayToEdit.cpp
 create mode 100644 src/widgets/PayToEdit.h

diff --git a/src/appcontext.cpp b/src/appcontext.cpp
index dd91c00..e0fa022 100644
--- a/src/appcontext.cpp
+++ b/src/appcontext.cpp
@@ -178,7 +178,7 @@ void AppContext::initWS() {
     this->ws->start();
 }
 
-void AppContext::onCancelTransaction(PendingTransaction *tx, const QString &address) {
+void AppContext::onCancelTransaction(PendingTransaction *tx, const QVector<QString> &address) {
     // tx cancelled by user
     double amount = tx->amount() / globals::cdiv;
     emit createTransactionCancelled(address, amount);
@@ -239,6 +239,30 @@ void AppContext::onCreateTransaction(const QString &address, quint64 amount, con
     emit initiateTransaction();
 }
 
+void AppContext::onCreateTransactionMultiDest(const QVector<QString> &addresses, const QVector<quint64> &amounts, const QString &description) {
+    this->tmpTxDescription = description;
+
+    if (this->currentWallet == nullptr) {
+        emit createTransactionError("Cannot create transaction; no wallet loaded");
+        return;
+    }
+
+    quint64 total_amount = 0;
+    for (auto &amount : amounts) {
+        total_amount += amount;
+    }
+
+    auto unlocked_balance = this->currentWallet->unlockedBalance();
+    if (total_amount > unlocked_balance) {
+        emit createTransactionError("Not enough money to spend");
+    }
+
+    qDebug() << "Creating tx";
+    this->currentWallet->createTransactionMultiDestAsync(addresses, amounts, this->tx_priority);
+
+    emit initiateTransaction();
+}
+
 void AppContext::onCreateTransactionError(const QString &msg) {
     this->tmpTxDescription = "";
     emit endTransaction();
@@ -750,15 +774,18 @@ void AppContext::onHeightRefreshed(quint64 walletHeight, quint64 daemonHeight, q
     }
 }
 
-void AppContext::onTransactionCreated(PendingTransaction *tx, const QString &address, const QString &paymentId, quint32 mixin) {
-    if(address == this->donationAddress)
-        this->donationSending = true;
+void AppContext::onTransactionCreated(PendingTransaction *tx, const QVector<QString> &address) {
+    for (auto &addr : address) {
+        if (addr == this->donationAddress) {
+            this->donationSending = true;
+        }
+    }
 
     // Let UI know that the transaction was constructed
     emit endTransaction();
 
     // tx created, but not sent yet. ask user to verify first.
-    emit createTransactionSuccess(tx, address, mixin);
+    emit createTransactionSuccess(tx, address);
 }
 
 void AppContext::onTransactionCommitted(bool status, PendingTransaction *tx, const QStringList& txid){
diff --git a/src/appcontext.h b/src/appcontext.h
index 68d0d82..f971129 100644
--- a/src/appcontext.h
+++ b/src/appcontext.h
@@ -115,7 +115,8 @@ public slots:
     void onOpenWallet(const QString& path, const QString &password);
     void onCreateTransaction(const QString &address, quint64 amount, const QString &description, bool all);
     void onCreateTransaction(XmrToOrder *order);
-    void onCancelTransaction(PendingTransaction *tx, const QString &address);
+    void onCreateTransactionMultiDest(const QVector<QString> &addresses, const QVector<quint64> &amounts, const QString &description);
+    void onCancelTransaction(PendingTransaction *tx, const QVector<QString> &address);
     void onSweepOutput(const QString &keyImage, QString address, bool churn, int outputs) const;
     void onCreateTransactionError(const QString &msg);
     void onOpenAliasResolve(const QString &openAlias);
@@ -136,7 +137,7 @@ private slots:
     void onWalletOpened(Wallet *wallet);
     void onWalletNewBlock(quint64 blockheight, quint64 targetHeight);
     void onHeightRefreshed(quint64 walletHeight, quint64 daemonHeight, quint64 targetHeight);
-    void onTransactionCreated(PendingTransaction *tx, const QString &address, const QString &paymentId, quint32 mixin);
+    void onTransactionCreated(PendingTransaction *tx, const QVector<QString> &address);
     void onTransactionCommitted(bool status, PendingTransaction *t, const QStringList& txid);
 
 signals:
@@ -159,8 +160,8 @@ signals:
     void walletOpenPasswordNeeded(bool invalidPassword, QString path);
     void transactionCommitted(bool status, PendingTransaction *tx, const QStringList& txid);
     void createTransactionError(QString message);
-    void createTransactionCancelled(QString address, double amount);
-    void createTransactionSuccess(PendingTransaction *tx, const QString &address, const quint32 &mixin);
+    void createTransactionCancelled(const QVector<QString> &address, double amount);
+    void createTransactionSuccess(PendingTransaction *tx, const QVector<QString> &address);
     void redditUpdated(QList<QSharedPointer<RedditPost>> &posts);
     void nodesUpdated(QList<QSharedPointer<FeatherNode>> &nodes);
     void ccsUpdated(QList<QSharedPointer<CCSEntry>> &entries);
diff --git a/src/dialog/txconfadvdialog.ui b/src/dialog/txconfadvdialog.ui
index 86df777..38f3cbc 100644
--- a/src/dialog/txconfadvdialog.ui
+++ b/src/dialog/txconfadvdialog.ui
@@ -185,17 +185,11 @@
    <item>
     <widget class="QTextEdit" name="outputs">
      <property name="sizePolicy">
-      <sizepolicy hsizetype="Expanding" vsizetype="Maximum">
+      <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
        <horstretch>0</horstretch>
        <verstretch>0</verstretch>
       </sizepolicy>
      </property>
-     <property name="maximumSize">
-      <size>
-       <width>16777215</width>
-       <height>100</height>
-      </size>
-     </property>
      <property name="readOnly">
       <bool>true</bool>
      </property>
diff --git a/src/dialog/txconfdialog.cpp b/src/dialog/txconfdialog.cpp
index 4d8d8a6..b088c5d 100644
--- a/src/dialog/txconfdialog.cpp
+++ b/src/dialog/txconfdialog.cpp
@@ -9,14 +9,13 @@
 
 #include <QMessageBox>
 
-TxConfDialog::TxConfDialog(AppContext *ctx, PendingTransaction *tx, const QString &address, const QString &description, int mixin, QWidget *parent)
+TxConfDialog::TxConfDialog(AppContext *ctx, PendingTransaction *tx, const QString &address, const QString &description, QWidget *parent)
         : QDialog(parent)
         , ui(new Ui::TxConfDialog)
         , m_ctx(ctx)
         , m_tx(tx)
         , m_address(address)
         , m_description(description)
-        , m_mixin(mixin)
 {
     ui->setupUi(this);
 
diff --git a/src/dialog/txconfdialog.h b/src/dialog/txconfdialog.h
index b4bb7d1..0fdd95a 100644
--- a/src/dialog/txconfdialog.h
+++ b/src/dialog/txconfdialog.h
@@ -18,7 +18,7 @@ class TxConfDialog : public QDialog
 Q_OBJECT
 
 public:
-    explicit TxConfDialog(AppContext *ctx, PendingTransaction *tx, const QString &address, const QString &description, int mixin, QWidget *parent = nullptr);
+    explicit TxConfDialog(AppContext *ctx, PendingTransaction *tx, const QString &address, const QString &description, QWidget *parent = nullptr);
     ~TxConfDialog() override;
 
     bool showAdvanced = false;
@@ -31,7 +31,6 @@ private:
     PendingTransaction *m_tx;
     QString m_address;
     QString m_description;
-    int m_mixin;
 };
 
 #endif //FEATHER_TXCONFDIALOG_H
diff --git a/src/libwalletqt/Wallet.cpp b/src/libwalletqt/Wallet.cpp
index 7e5816a..c1100ae 100644
--- a/src/libwalletqt/Wallet.cpp
+++ b/src/libwalletqt/Wallet.cpp
@@ -591,7 +591,40 @@ void Wallet::createTransactionAsync(const QString &dst_addr, const QString &paym
 {
     m_scheduler.run([this, dst_addr, payment_id, amount, mixin_count, priority] {
         PendingTransaction *tx = createTransaction(dst_addr, payment_id, amount, mixin_count, priority);
-        emit transactionCreated(tx, dst_addr, payment_id, mixin_count);
+        QVector<QString> address {dst_addr};
+        emit transactionCreated(tx, address);
+    });
+}
+
+PendingTransaction* Wallet::createTransactionMultiDest(const QVector<QString> &dst_addr, const QVector<quint64> &amount,
+                                                       PendingTransaction::Priority priority)
+{
+    std::vector<std::string> dests;
+    for (auto &addr : dst_addr) {
+        dests.push_back(addr.toStdString());
+    }
+
+    std::vector<uint64_t> amounts;
+    for (auto &a : amount) {
+        amounts.push_back(a);
+    }
+
+    // TODO: remove mixin count
+    Monero::PendingTransaction * ptImpl = m_walletImpl->createTransactionMultDest(dests, "", amounts, 11, static_cast<Monero::PendingTransaction::Priority>(priority));
+    PendingTransaction * result = new PendingTransaction(ptImpl);
+    return result;
+}
+
+void Wallet::createTransactionMultiDestAsync(const QVector<QString> &dst_addr, const QVector<quint64> &amount,
+                                             PendingTransaction::Priority priority)
+{
+    m_scheduler.run([this, dst_addr, amount, priority] {
+        PendingTransaction *tx = createTransactionMultiDest(dst_addr, amount, priority);
+        QVector<QString> addresses;
+        for (auto &addr : dst_addr) {
+            addresses.push_back(addr);
+        }
+        emit transactionCreated(tx, addresses);
     });
 }
 
@@ -612,7 +645,8 @@ void Wallet::createTransactionAllAsync(const QString &dst_addr, const QString &p
 {
     m_scheduler.run([this, dst_addr, payment_id, mixin_count, priority] {
         PendingTransaction *tx = createTransactionAll(dst_addr, payment_id, mixin_count, priority);
-        emit transactionCreated(tx, dst_addr, payment_id, mixin_count);
+        QVector<QString> address {dst_addr};
+        emit transactionCreated(tx, address);
     });
 }
 
@@ -630,7 +664,8 @@ void Wallet::createTransactionSingleAsync(const QString &key_image, const QStrin
 {
     m_scheduler.run([this, key_image, dst_addr, outputs, priority] {
         PendingTransaction *tx = createTransactionSingle(key_image, dst_addr, outputs, priority);
-        emit transactionCreated(tx, dst_addr, "", 10); // todo: return true mixincount
+        QVector<QString> address {dst_addr};
+        emit transactionCreated(tx, address);
     });
 }
 
@@ -645,7 +680,8 @@ void Wallet::createSweepUnmixableTransactionAsync()
 {
     m_scheduler.run([this] {
         PendingTransaction *tx = createSweepUnmixableTransaction();
-        emit transactionCreated(tx, "", "", 0);
+        QVector<QString> address {""};
+        emit transactionCreated(tx, address);
     });
 }
 
diff --git a/src/libwalletqt/Wallet.h b/src/libwalletqt/Wallet.h
index b825929..e8f1e19 100644
--- a/src/libwalletqt/Wallet.h
+++ b/src/libwalletqt/Wallet.h
@@ -266,6 +266,15 @@ public:
                                             quint64 amount, quint32 mixin_count,
                                             PendingTransaction::Priority priority);
 
+    //! creates multi-destination transaction
+    Q_INVOKABLE PendingTransaction * createTransactionMultiDest(const QVector<QString> &dst_addr, const QVector<quint64> &amount,
+                                                                PendingTransaction::Priority priority);
+
+    //! creates async multi-destination transaction
+    Q_INVOKABLE void createTransactionMultiDestAsync(const QVector<QString> &dst_addr, const QVector<quint64> &amount,
+                                                     PendingTransaction::Priority priority);
+
+
     //! creates transaction with all outputs
     Q_INVOKABLE PendingTransaction * createTransactionAll(const QString &dst_addr, const QString &payment_id,
                                                           quint32 mixin_count, PendingTransaction::Priority priority);
@@ -449,7 +458,7 @@ signals:
     void deviceShowAddressShowed();
 
     // emitted when transaction is created async
-    void transactionCreated(PendingTransaction * transaction, QString address, QString paymentId, quint32 mixinCount);
+    void transactionCreated(PendingTransaction * transaction, QVector<QString> address);
 
     void connectionStatusChanged(int status) const;
     void currentSubaddressAccountChanged() const;
diff --git a/src/main.cpp b/src/main.cpp
index e3db53d..e3d56ba 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -161,6 +161,7 @@ if (AttachConsole(ATTACH_PARENT_PROCESS)) {
 #endif
 
     qInstallMessageHandler(Utils::applicationLogHandler);
+    qRegisterMetaType<QVector<QString>>();
 
     auto *mainWindow = new MainWindow(ctx);
     return QApplication::exec();
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index c0b3044..fea615c 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -74,6 +74,7 @@ MainWindow::MainWindow(AppContext *ctx, QWidget *parent) :
     connect(ui->actionQuit, &QAction::triggered, this, &MainWindow::menuQuitClicked);
     connect(ui->actionSettings, &QAction::triggered, this, &MainWindow::menuSettingsClicked);
     connect(ui->actionCalculator, &QAction::triggered, this, &MainWindow::showCalcWindow);
+    connect(ui->actionPay_to_many, &QAction::triggered, this, &MainWindow::payToMany);
     connect(ui->actionWallet_cache_debug, &QAction::triggered, this, &MainWindow::showWalletCacheDebugDialog);
 
 #if defined(Q_OS_WIN) || defined(Q_OS_MACOS)
@@ -153,6 +154,7 @@ MainWindow::MainWindow(AppContext *ctx, QWidget *parent) :
 
     // Send widget
     connect(ui->sendWidget, &SendWidget::createTransaction, m_ctx, QOverload<const QString &, quint64, const QString &, bool>::of(&AppContext::onCreateTransaction));
+    connect(ui->sendWidget, &SendWidget::createTransactionMultiDest, m_ctx, &AppContext::onCreateTransactionMultiDest);
 
     // Nodes
     connect(m_ctx->nodes, &Nodes::nodeExhausted, this, &MainWindow::showNodeExhaustedMessage);
@@ -737,7 +739,7 @@ void MainWindow::onConnectionStatusChanged(int status)
     m_statusBtnConnectionStatusIndicator->setIcon(QIcon(statusIcon));
 }
 
-void MainWindow::onCreateTransactionSuccess(PendingTransaction *tx, const QString &address, const quint32 &mixin) {
+void MainWindow::onCreateTransactionSuccess(PendingTransaction *tx, const QVector<QString> &address) {
     auto tx_status = tx->status();
     auto err = QString("Can't create transaction: ");
 
@@ -761,7 +763,16 @@ void MainWindow::onCreateTransactionSuccess(PendingTransaction *tx, const QStrin
     } else {
         const auto &description = m_ctx->tmpTxDescription;
 
-        auto *dialog = new TxConfDialog(m_ctx, tx, address, description, mixin, this);
+        // Show advanced dialog on multi-destination transactions
+        if (address.size() > 1) {
+            auto *dialog_adv = new TxConfAdvDialog(m_ctx, description, this);
+            dialog_adv->setTransaction(tx);
+            dialog_adv->exec();
+            dialog_adv->deleteLater();
+            return;
+        }
+
+        auto *dialog = new TxConfDialog(m_ctx, tx, address[0], description, this);
         switch (dialog->exec()) {
             case QDialog::Rejected:
             {
@@ -1061,6 +1072,15 @@ void MainWindow::showCalcWindow() {
     m_windowCalc->show();
 }
 
+void MainWindow::payToMany() {
+    ui->tabWidget->setCurrentIndex(Tabs::SEND);
+    ui->sendWidget->payToMany();
+    QMessageBox::information(this, "Pay to many", "Enter a list of outputs in the 'Pay to' field.\n"
+                                                  "One output per line.\n"
+                                                  "Format: address, amount\n"
+                                                  "A maximum of 16 addresses may be specified.");
+}
+
 void MainWindow::showSendScreen(const CCSEntry &entry) {
     ui->sendWidget->fill(entry);
     ui->tabWidget->setCurrentIndex(Tabs::SEND);
diff --git a/src/mainwindow.h b/src/mainwindow.h
index 4016f22..fc6257c 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -104,6 +104,7 @@ public slots:
     void showViewOnlyDialog();
     void donateButtonClicked();
     void showCalcWindow();
+    void payToMany();
     void showWalletCacheDebugDialog();
     void showSendTab();
     void showHistoryTab();
@@ -141,7 +142,7 @@ public slots:
     void onWalletClosed(WalletWizard::Page page = WalletWizard::Page_Menu);
     void onConnectionStatusChanged(int status);
     void onCreateTransactionError(const QString &message);
-    void onCreateTransactionSuccess(PendingTransaction *tx, const QString &address, const quint32 &mixin);
+    void onCreateTransactionSuccess(PendingTransaction *tx, const QVector<QString> &address);
     void onTransactionCommitted(bool status, PendingTransaction *tx, const QStringList& txid);
 
 signals:
diff --git a/src/mainwindow.ui b/src/mainwindow.ui
index a1e2b4f..bb51edb 100644
--- a/src/mainwindow.ui
+++ b/src/mainwindow.ui
@@ -190,7 +190,7 @@
         <item>
          <widget class="SendWidget" name="sendWidget" native="true">
           <property name="sizePolicy">
-           <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+           <sizepolicy hsizetype="Preferred" vsizetype="Maximum">
             <horstretch>0</horstretch>
             <verstretch>0</verstretch>
            </sizepolicy>
@@ -446,6 +446,7 @@
     <addaction name="menuLoad_signed_transaction"/>
     <addaction name="actionImport_transaction"/>
     <addaction name="separator"/>
+    <addaction name="actionPay_to_many"/>
     <addaction name="actionCalculator"/>
     <addaction name="actionCreateDesktopEntry"/>
    </widget>
@@ -726,6 +727,11 @@
     <string>Wallet cache debug</string>
    </property>
   </action>
+  <action name="actionPay_to_many">
+   <property name="text">
+    <string>Pay to many</string>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <customwidgets>
diff --git a/src/sendwidget.cpp b/src/sendwidget.cpp
index 5e0b883..141ea84 100644
--- a/src/sendwidget.cpp
+++ b/src/sendwidget.cpp
@@ -24,8 +24,8 @@ SendWidget::SendWidget(QWidget *parent) :
     connect(ui->btnClear, &QPushButton::clicked, this, &SendWidget::clearClicked);
     connect(ui->btnMax, &QPushButton::clicked, this, &SendWidget::btnMaxClicked);
     connect(ui->comboCurrencySelection, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &SendWidget::currencyComboChanged);
-    connect(ui->lineAmount, &QLineEdit::textEdited, this, &SendWidget::amountEdited);
-    connect(ui->lineAddress, &QLineEdit::textEdited, this, &SendWidget::addressEdited);
+    connect(ui->lineAmount, &QLineEdit::textChanged, this, &SendWidget::amountEdited);
+    connect(ui->lineAddress, &QPlainTextEdit::textChanged, this, &SendWidget::addressEdited);
     connect(ui->btn_openAlias, &QPushButton::clicked, this, &SendWidget::aliasClicked);
     ui->label_conversionAmount->setText("");
     ui->label_conversionAmount->hide();
@@ -41,6 +41,7 @@ SendWidget::SendWidget(QWidget *parent) :
                                   "You will be able to review the transaction fee before the transaction is broadcast.\n\n"
                                   "To send all your balance, click the Max button to the right.");
 
+    ui->lineAddress->setNetType(m_ctx->networkType);
     this->setupComboBox();
 }
 
@@ -50,8 +51,22 @@ void SendWidget::currencyComboChanged(int index) {
     this->amountEdited(amount);
 }
 
-void SendWidget::addressEdited(const QString &text) {
-    text.contains(".") ? ui->btn_openAlias->show() : ui->btn_openAlias->hide();
+void SendWidget::addressEdited() {
+    QVector<PartialTxOutput> outputs = ui->lineAddress->getOutputs();
+
+    bool freezeAmounts = outputs.size() > 0;
+
+    ui->lineAmount->setReadOnly(freezeAmounts);
+    ui->lineAmount->setFrame(!freezeAmounts);
+    ui->btnMax->setDisabled(freezeAmounts);
+
+    if (outputs.size() > 0) {
+        ui->lineAmount->setText(WalletManager::displayAmount(ui->lineAddress->getTotal()));
+    } else {
+        ui->lineAmount->setText("");
+    }
+
+    ui->btn_openAlias->setVisible(ui->lineAddress->isOpenAlias());
 }
 
 void SendWidget::amountEdited(const QString &text) {
@@ -69,7 +84,9 @@ void SendWidget::fill(double amount) {
 void SendWidget::fill(const QString &address, const QString &description, double amount) {
     ui->lineDescription->setText(description);
     ui->lineAddress->setText(address);
-    ui->lineAddress->setCursorPosition(0);
+
+    ui->lineAddress->moveCursor(QTextCursor::Start);
+
     if (amount > 0)
         ui->lineAmount->setText(QString::number(amount));
     this->updateConversionLabel();
@@ -77,7 +94,7 @@ void SendWidget::fill(const QString &address, const QString &description, double
 
 void SendWidget::fillAddress(const QString &address) {
     ui->lineAddress->setText(address);
-    ui->lineAddress->setCursorPosition(0);
+    ui->lineAddress->moveCursor(QTextCursor::Start);
 }
 
 void SendWidget::sendClicked() {
@@ -96,6 +113,35 @@ void SendWidget::sendClicked() {
         return;
     }
 
+    QVector<PartialTxOutput> outputs = ui->lineAddress->getOutputs();
+    QVector<PayToLineError> errors = ui->lineAddress->getErrors();
+    if (errors.size() > 0 && ui->lineAddress->isMultiline()) {
+        QString errorText;
+        for (auto &error: errors) {
+            errorText += QString("Line #%1:\n%2\n").arg(QString::number(error.idx + 1), error.error);
+        }
+
+        QMessageBox::warning(this, "Warning", QString("Invalid lines found:\n\n%1").arg(errorText));
+        return;
+    }
+
+    if (outputs.size() > 0) { // multi destination transaction
+        if (outputs.size() > 16) {
+            QMessageBox::warning(this, "Warning", "Maximum number of outputs (16) exceeded.");
+            return;
+        }
+
+        QVector<QString> addresses;
+        QVector<quint64> amounts;
+        for (auto &output : outputs) {
+            addresses.push_back(output.address);
+            amounts.push_back(output.amount);
+        }
+
+        emit createTransactionMultiDest(addresses, amounts, description);
+        return;
+    }
+
     quint64 amount;
     if (currency == "XMR") {
         amount = this->amount();
@@ -193,6 +239,10 @@ void SendWidget::clearFields() {
     ui->label_conversionAmount->clear();
 }
 
+void SendWidget::payToMany() {
+    ui->lineAddress->payToMany();
+}
+
 void SendWidget::onWalletClosed() {
     this->clearFields();
     ui->btnSend->setEnabled(true);
diff --git a/src/sendwidget.h b/src/sendwidget.h
index 91bac4b..0821f01 100644
--- a/src/sendwidget.h
+++ b/src/sendwidget.h
@@ -22,6 +22,7 @@ public:
     void fill(const QString &address, const QString& description, double amount = 0);
     void fill(double amount);
     void clearFields();
+    void payToMany();
     ~SendWidget() override;
 
 public slots:
@@ -30,7 +31,7 @@ public slots:
     void aliasClicked();
     void btnMaxClicked();
     void amountEdited(const QString &text);
-    void addressEdited(const QString &text);
+    void addressEdited();
     void currencyComboChanged(int index);
     void fillAddress(const QString &address);
     void updateConversionLabel();
@@ -45,6 +46,7 @@ public slots:
 signals:
     void resolveOpenAlias(const QString &address);
     void createTransaction(const QString &address, quint64 amount, const QString &description, bool all);
+    void createTransactionMultiDest(const QVector<QString> &addresses, const QVector<quint64> &amounts, const QString &description);
 
 private:
     void setupComboBox();
diff --git a/src/sendwidget.ui b/src/sendwidget.ui
index 8e5464e..b5b3810 100644
--- a/src/sendwidget.ui
+++ b/src/sendwidget.ui
@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>647</width>
-    <height>175</height>
+    <height>231</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -46,11 +46,7 @@
     </widget>
    </item>
    <item row="0" column="1">
-    <widget class="QLineEdit" name="lineAddress">
-     <property name="text">
-      <string/>
-     </property>
-    </widget>
+    <widget class="PayToEdit" name="lineAddress"/>
    </item>
    <item row="1" column="0">
     <widget class="HelpLabel" name="label_Description">
@@ -190,6 +186,11 @@
    <extends>QLabel</extends>
    <header>components.h</header>
   </customwidget>
+  <customwidget>
+   <class>PayToEdit</class>
+   <extends>QPlainTextEdit</extends>
+   <header>widgets/PayToEdit.h</header>
+  </customwidget>
  </customwidgets>
  <resources/>
  <connections/>
diff --git a/src/utils/xmrtoorder.cpp b/src/utils/xmrtoorder.cpp
index 75f382a..36011dd 100644
--- a/src/utils/xmrtoorder.cpp
+++ b/src/utils/xmrtoorder.cpp
@@ -24,9 +24,9 @@ XmrToOrder::XmrToOrder(AppContext *ctx, UtilsNetworking *network, QString baseUr
     connect(m_ctx, &AppContext::createTransactionCancelled, this, &XmrToOrder::onTransactionCancelled);
 }
 
-void XmrToOrder::onTransactionCancelled(const QString &address, double amount) {
+void XmrToOrder::onTransactionCancelled(const QVector<QString> &address, double amount) {
     // listener for all cancelled transactions - will try to match the exact amount to this order.
-    if(this->incoming_amount_total != amount || this->receiving_subaddress != address) return;
+    if(this->incoming_amount_total != amount || this->receiving_subaddress != address[0]) return;
 
     this->errorMsg = "TX cancelled by user";
     this->changeState(OrderState::Status_OrderFailed);
diff --git a/src/utils/xmrtoorder.h b/src/utils/xmrtoorder.h
index b3b8dce..ae585d3 100644
--- a/src/utils/xmrtoorder.h
+++ b/src/utils/xmrtoorder.h
@@ -66,7 +66,7 @@ public:
 
 public slots:
     void onCountdown();
-    void onTransactionCancelled(const QString &address, double amount);
+    void onTransactionCancelled(const QVector<QString> &address, double amount);
     void onTransactionCommitted(bool status, PendingTransaction *tx, const QStringList& txid);
 
     void onCreatedError();
diff --git a/src/widgets/PayToEdit.cpp b/src/widgets/PayToEdit.cpp
new file mode 100644
index 0000000..f19a6e3
--- /dev/null
+++ b/src/widgets/PayToEdit.cpp
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright (c) 2020-2021, The Monero Project.
+// Copyright (c) 2012 thomasv@gitorious
+
+#include "PayToEdit.h"
+
+#include <QtGlobal>
+#include <QScrollBar>
+
+#include "utils/utils.h"
+#include "model/ModelUtils.h"
+
+#include "libwalletqt/WalletManager.h"
+
+PayToEdit::PayToEdit(QWidget *parent) : QPlainTextEdit(parent)
+{
+    this->setFont(ModelUtils::getMonospaceFont());
+
+    connect(this->document(), &QTextDocument::contentsChanged, this, &PayToEdit::updateSize);
+    connect(this, &QPlainTextEdit::textChanged, this, &PayToEdit::checkText);
+
+    this->updateSize();
+}
+
+void PayToEdit::setNetType(NetworkType::Type netType) {
+    m_netType = netType;
+}
+
+void PayToEdit::setText(const QString &text) {
+    this->setPlainText(text);
+}
+
+QString PayToEdit::text() {
+    return this->toPlainText();
+}
+
+QVector<PayToLineError> PayToEdit::getErrors() {
+    return m_errors;
+}
+
+QVector<PartialTxOutput> PayToEdit::getOutputs() {
+    return m_outputs;
+}
+
+quint64 PayToEdit::getTotal() {
+    return m_total;
+}
+
+QStringList PayToEdit::lines() {
+    return this->toPlainText().split("\n");
+}
+
+bool PayToEdit::isMultiline() {
+    return this->lines().size() > 1;
+}
+
+void PayToEdit::payToMany() {
+    this->setPlainText("\n\n\n");
+    this->updateSize();
+}
+
+bool PayToEdit::isOpenAlias() {
+    if (this->isMultiline()) {
+        return false;
+    }
+    auto text = this->toPlainText().trimmed();
+    if (!(text.contains('.') and (!text.contains(' ')))) {
+        return false;
+    }
+    auto parts = text.split(',');
+    if (parts.size() > 0 and WalletManager::addressValid(parts[0], m_netType)) {
+        return false;
+    }
+    return true;
+}
+
+void PayToEdit::checkText() {
+    m_errors.clear();
+    m_outputs.clear();
+
+    // filter out empty lines
+    QStringList lines;
+    for (auto &l : this->lines()) {
+        if (!l.isEmpty()) {
+            lines.push_back(l);
+        }
+    }
+
+    this->parseAsMultiline(lines);
+}
+
+void PayToEdit::updateSize() {
+    qreal lineHeight = QFontMetrics(this->document()->defaultFont()).height();
+    qreal docHeight = this->document()->size().height();
+    int h = int(docHeight * lineHeight + 11);
+    h = qMin(qMax(h, m_heightMin), m_heightMax);
+    this->setMinimumHeight(h);
+    this->setMaximumHeight(h);
+    this->verticalScrollBar()->hide();
+}
+
+PartialTxOutput PayToEdit::parseAddressAndAmount(const QString &line) {
+    QStringList x = line.split(",");
+    if (x.size() != 2) {
+        return PartialTxOutput();
+    }
+
+    QString address = this->parseAddress(x[0]);
+    quint64 amount = this->parseAmount(x[1]);
+
+    return PartialTxOutput(address, amount);
+}
+
+quint64 PayToEdit::parseAmount(QString amount) {
+    amount.replace(',', '.');
+    if (amount.isEmpty()) return 0;
+
+    return WalletManager::amountFromString(amount.trimmed());
+}
+
+QString PayToEdit::parseAddress(QString address) {
+    if (!WalletManager::addressValid(address.trimmed(), m_netType)) {
+        return "";
+    }
+    return address;
+}
+
+void PayToEdit::parseAsMultiline(const QStringList &lines) {
+    m_outputs.clear();
+    m_total = 0;
+
+    int i = 0;
+    for (auto &line : lines) {
+        PartialTxOutput output = this->parseAddressAndAmount(line);
+        if (output.address.isEmpty() && output.amount == 0) {
+            m_errors.append(PayToLineError(line, "Expected two comma-separated values: (address, amount)", i, true));
+            continue;
+        } else if (output.address.isEmpty()) {
+            m_errors.append(PayToLineError(line, "Invalid address", i, true));
+            continue;
+        } else if (output.amount == 0) {
+            m_errors.append(PayToLineError(line, "Invalid amount", i, true));
+            continue;
+        }
+
+        m_outputs.append(output);
+        m_total += output.amount;
+        i += 1;
+    }
+}
\ No newline at end of file
diff --git a/src/widgets/PayToEdit.h b/src/widgets/PayToEdit.h
new file mode 100644
index 0000000..78ffd23
--- /dev/null
+++ b/src/widgets/PayToEdit.h
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright (c) 2020-2021, The Monero Project.
+// Copyright (c) 2012 thomasv@gitorious
+
+#ifndef FEATHER_PAYTOEDIT_H
+#define FEATHER_PAYTOEDIT_H
+
+#include <QObject>
+#include <QPlainTextEdit>
+
+#include "utils/utils.h"
+
+struct PartialTxOutput {
+    explicit PartialTxOutput(QString address = "", quint64 amount = 0)
+        : address(address), amount(amount) {}
+
+    QString address;
+    quint64 amount;
+};
+
+struct PayToLineError {
+    explicit PayToLineError(QString lineContent, QString error, int idx = 0, bool isMultiline = false)
+        : lineContent(lineContent), error(error), idx(idx), isMultiline(isMultiline) {}
+
+    QString lineContent;
+    QString error;
+    int idx;
+    bool isMultiline;
+};
+
+class PayToEdit : public QPlainTextEdit
+{
+Q_OBJECT
+
+public:
+    explicit PayToEdit(QWidget *parent = nullptr);
+
+    void setNetType(NetworkType::Type netType);
+    void setText(const QString &text);
+    QString text();
+
+    QVector<PayToLineError> getErrors();
+    QVector<PartialTxOutput> getOutputs();
+    quint64 getTotal();
+
+    QStringList lines();
+    bool isMultiline();
+    void payToMany();
+    bool isOpenAlias();
+
+private:
+    void checkText();
+    void updateSize();
+
+    PartialTxOutput parseAddressAndAmount(const QString &line);
+    quint64 parseAmount(QString amount);
+    QString parseAddress(QString address);
+
+    void parseAsMultiline(const QStringList &lines);
+
+    int m_heightMin = 0;
+    int m_heightMax = 150;
+    quint64 m_total = 0;
+    NetworkType::Type m_netType = NetworkType::Type::MAINNET;
+
+    QVector<PayToLineError> m_errors;
+    QVector<PartialTxOutput> m_outputs;
+};
+
+#endif //FEATHER_PAYTOEDIT_H